Predisposing risk factors for MSD.
Reducing risk factors for MSD.
Slips, Trips and Falls.
Ergonomics is the scientific study of human at work.
Ergonomic principles adapt work to a specific person
by designing tasks & tools or equipment to fit the
individual to prevent injuries to the musculoskeletal
system (Verhagen et al. 2006).
Significance of ergonomics.
•Reduction of work-related injuries
•Increased worker productivity
•Increased work quality
Ergonomics provides a win-win
An “MSD” is an illness or injury that affects one or
more parts of the musculoskeletal system
Other common terms for “MSDs”are:
Cumulative trauma disorder (CTD’s)
Repetitive strain injures (RSI’s)
Repetitive motion injuries (RMI’s)
When not diagnosed and treated these can cause
inconvenience permanent pain and disability.
Implications of poor ergonomics.
Signs of MSD
Decreased range of
Loss of function
Loss of color
Loss of balance
What are MSD’S?
MSD’s are injuries caused by sustained
exposure to stressors or repetitive motion
(English et al. 1995).
They may affect muscles, tendons, ligaments,
bones, blood vessels, or nerves.
Some well-known MSD’s are:
Carpel tunnel syndrome
CARPAL TUNNEL SYNDROME
The median nerve does not work properly due to pressure on the
nerve as it runs through an opening called the carpel tunnel
Numbness is usually first symptom.
Pain & tingling, can go up the arm to the
shoulder and neck, causing waking
to pain in middle of night
GUYON’S CANAL SYNDROME
Guyon’s affects the ulnar nerve
as it passes through the Guyon
canal in the wrist; this is similar
to carpal tunnel, but involves a
different nerve (Davis et al.1998)
Unlike carpel tunnel, Guyon’s
affects the little and ring fingers.
Can be in conjunction with carpal tunnel
Trigger finger affects the ability of tendons to
slip back and forth. The tendon and/or
ligament thicken and a nodule forms
This can be caused by rheumatoid arthritis,
lacerations of tendon, gripping power tools,
long hours of grasping steering wheel, or birth
defects (Aaras 1994).
Symptoms are pain and
a funny clicking sensation
Overuse or misuse of the forearm muscles can cause tendonitis,
or a painful inflammation of the tendons connecting these
muscles to bone (English et al. (1995).
This condition is brought
on or aggravated by poor leverage
causing an uneven distribution
of force on a few muscles.
This may be when working,
or during certain leisure activities,
such as sports and gardening.
Symptom are severe pain.
ARE MSD’S PREVENTABLE?
They are preventable and reversible
….. if identified early.
The treatment depends on the stage of MSD.
If the condition cannot be reversed, treatment
can turn into a pain management situation.
The individual plays a large role
in preventing MSD’s.
Predisposing risk factors for MSD
…perform frequent repetitive motions?
…bend at the waist or twist when lifting objects?
…lift push or pull objects throughout the day?
…sometimes use the wrong tool for the job?
…grasp tools with your fingers?
…forget to take breaks while working?
…feel like you are under stress?
…have to stretch to reach your work?
…forget to adjust your work area to fit your task?
The more you answered “yes”, the greater your risk.
RISK FACTORS which can lead to MSDs
Static loading or sustained exertion
Repetition of same motion for several hours/day
Length of tasks without breaks
Insufficient rest time
These STRESSORS can be influenced by
1. Organizational or administrative precautions
2. Environmental conditions
3. Individual work routine and habits
Most MSDs are the result of combined risk factors
Reducing RISK FACTORS for MSDs
The purpose of ergonomic training is to
help you reduce or eliminate the stresses
that can lead to MSDs (Schierhout et al.
Your body is designed to do work. When
it works in positions or postures in which
it is designed to deal with physical stress,
there is no problem, but when it is forced
to perform under unnatural situations or
for abnormal periods of time, injuries can
Almost all of the ergonomic stresses at
work can be decreased by using the right
equipment in the right position so that the
body can perform in the right posture.
Review your Work Area
•You spend most of your day in
your work area.
•You don’t want your work area to
contribute to ergonomic problems
•Ergonomic Rule #1
Use a good CHAIR (adapted from Ando et al 2004)
Front edge of seat pan
Five feet for base-most stable
Seat pan adjustable
Backrest provides good lower back support
The position of your head and neck is very important
Place computer monitors
directly in front of you
The right height is person
dependent- usually the top
of the screen at eye level
(or slightly below for those who
The screen should be at least an arms length away
(If you can’t see at that distance, get special computer glasses)
Raise the monitor if you
have to look down at it
Position equipment so that your body is in a comfortable and
natural position most of the time while you are working.
Don’t place things so you have to reach, twist or bend continually
Place work at monitor height or place in path of monitor
Listen to your body. If you cannot focus or often feel tired or
uncomfortable, you are probably not working in a good position.
See what you can do to make your work more comfortable for
Disclaimer: Wait a minute! Though this position may look comfortable, it
is NOT a comfortable position to work in.
Imagine how your back would feel after typing a few pages in this position!
Do not equate comfortable leisure positions with comfortable work positions!
Everyone needs a relaxed, neutral position
DO WHAT’S COMFORTABLE FOR YOUR BODY!
Monitor at or below eye
Feet flat on the floor
Forearms and thighs parallel to the
Mouse should be
close to the
keyboard and the
same height or
Locate the mouse
to avoid reaching
Should be different for right and left handers
You should not have to twist and reach across your body
every time you answer the phone.
Many people need to spend a lot of time on the phone, and must
often do other tasks at the same time
This creates a lot of stress
for neck and shoulder muscles
Consider a head set if you spend a lot of time on the phone,
especially if you do other tasks at the same time
LIGHTING & MONITOR GLARE
Lighting should be
indirect and adequate
Not too much light,
or it may cause a glare,
headaches and eye
If there is a glare on your
eyes as you work, use
glare screens on
computers, or adjustable
blinds at windows
Ideal is 35-50 foot candles
Noise can be a STRESSOR
If your office is near a noise source,
close your door, or wear ear plugs
Besides causing ear damage, constant
noise can create extra muscle tension in
the body causing fatigue and making it
easier for ergonomic injuries to occur
(Westlander et al 1998).
People are more prone to ergonomic injuries
in cold environments. Muscles and other
tissues are more tense, because of decreased
circulation (Schierhout et al 1995)..
Do some warm up exercises, such as
stretching your hands, to loosen your finger
muscles before keyboarding.
MECHANICAL CONTACT STRESS
A hard or sharp surface or object pressing
into the soft tissues, the tendons, nerves
and blood vessels.
Resting wrists on the desk edge while typing or
Leaning elbows on hard chair or armrests or work
Sitting in chair that places pressure on the backs of
VIBRATION causes stress
Hand-arm vibration (hand power tools)
Whole body vibration (driving rough off roads)
Even if these do not occur in your work
environment, what about home activities?
What happens off the job may influence
stress, discomfort, or pain during the workday
and vise-versa.The two are intertwined.
Hobbies and recreational activities (golf,
sewing, gardening, etc.) may cause repetitive
motion injuries, which may then be
complicated on the job.
Any interactions, job tasks or personal problems
which cause psychological or social stress
cause increased muscle tension, which can
make injury more likely. Be aware of these
additional stresses and compensate for them
by taking extra breaks and being especially
careful when under extra pressure (Benard et
People face different stresses and have
different abilities to cope.
Employees vary in physical condition.
Some individuals are also dealing with
chronic illnesses or disabilities
We don’t live in a vacuum,
life stresses can adversely
effect the wellness of an
individual and contribute to
Individual work routine and habit
most STRESSORS can be minimized
by individual habits
and work routine.
The solution to most ergonomic
problems is to work comfortably
and avoid a few common
Prevention of workplace injuries
Performing the same or similar motions repeatedly for
extended periods without time for rest and recovery
can lead to discomfort or trauma (English et al. 1995).
Flipping through files & paperwork
Extended reading or writing
Punching or stapling
Pruning or clipping
AVOID LONG DURATION OF SAME TASK
The length of time spent on a task without
breaks, shifts in position, or stretches is more
important than the actual task.
The longer the uninterrupted duration of a
task, the more potential for discomfort or injury
Our bodies are designed to do work.
But the result on the body of doing a
repetitive task for 2 hours verses 6
hours straight is very different.
Stretch Break (default), is a software that interrupts you every 30 minutes-
suggests three varied stretches which take a total of 1 minute to
complete. You cannot believe how much better you feel afterwards (Van
den Heuvel et al 2003).
You can cancel the stretches as soon as they come on the screen,
choose the amount of time you work before being interrupted ( between
10 minutes and 3 hours) and decide which of the many exercises you
want to include, and how many you want to do at each break.
Such programs are one of the best preventions of ergonomic injuries at a
computer workstation. Even if you choose not to do the exercises, you will
be reminded to shift position, etc periodically so that your muscles do not
become unduly stressed. Most computer related injuries occur because
of projects which engage persons for a substantial length of time.
A FEW BREAK IDEAS
Organize tasks around built in breaks
Eye breaks - blink to moisten eyes every 5-10 minutes. Every 15
minutes or so look away from the screen to distant part of room.
Micro-breaks - between burst of activity rest the hands, neck and
shoulders in a relaxed straight posture.
Rest breaks - every 30-60 minutes take a brief 5-minute break
and engage in another activity.
Exercise breaks - every 1-2 hours do gentle stretching exercises
While seated, brace elbows on the edge
of the desk
Let weight fall forward
Cup hands over eyes and close eyes
Inhale slowly through nose & hold for 4
Continue deep breathing for 15-30
Close eyes and slowly & gently move
eyes up to the ceiling, then slowly down
to the floor
Repeat 3 times
Close eyes and slowly & gently move
eyes to the left, then slowly to the right
Repeat 3 times
Tilt ear towards shoulder
Reach up and touch top of head with
palm to hold in tilted position
Hold 5-10 seconds. Repeat 2-3 times
(come out of stretch slowly)
Reverse side and repeat
Pec Corner Stretch
Stand at a corner about a foot away from the
wall with forearms on opposite sides of the
corner. One foot should be forward.
Elbows should be at slightly below shoulder
Keep abdominals tight to avoid arching back
Lean gently towards corner by bending the
front knee until a stretch is felt in front of the
Hold 5-10 seconds. Repeat 2-3 times
Take a deep breathe and reach up over
head with both arms.
Hold 5-10 seconds
Exhale and lower slowly
Repeat 2-3 times
Place arms behind head being careful
not to press hand into head
Relax shoulders, and squeeze shoulder
blades together while keeping shoulders
back and down
Hold 5-10 seconds. Repeat 2-3 times
Chair Rotation Stretch
Sit in chair and place feet flat on floor
Reach across your body and grab the
back of the chair
Pull gently to increase stretch in mid
Hold 5-10 seconds. Repeat 5 times
Repeat on other side
Thoracic Spine Extension
Lie on your back with a pillow under your
knees. Place a firmly rolled towel under
your shoulder blades across your upper
Raise arms up as you inhale
Lower arms as you exhale, and hold a
couple of seconds
Do this 5 times
Prop Ups or Press Ups
Lie on stomach and either prop up on
forearms or if wrists are not compromised,
press up through hands.
Let stomach sag, and allow back to arch
without using back muscles.
If propped on elbows, hold 5-10 seconds.
Repeat 5 times
If on hands, press up and down slowly 10
Wrist Flexed & Extended
Hold arm straight at waist height
With fingers of other hand, gently press down
above the knuckles, bending wrist down. (DO
NOT hold at the fingers to push down.)
Hold 5-10 seconds and repeat 2-3 times
For extending, hold onto palm of hand and
stretch wrist back. (DO NOT pull on fingers.)
Hold 5-10 seconds and repeat 2-3 times.
Avoid BAD POSTURES
Bad postures are a primary cause of ergonomic injuries
Everyone has seen these….
Propping a phone on shoulder
Slouching over a computer
Avoid AWKARD POSITIONS
Awkward positions bend the joints in a way that
they are more likely to become injured.
Reaching up and over
Slouching or leaning forward in the chair
Leaning forward or bending over work
Holding heavy items in position
Lifting, pushing pulling
Turning head side to side to view the monitor
Cradling the phone between the ear and shoulder
Typing with bent wrists
Avoid SUSTAINED EXERTIONS
Static loading occurs when muscles must hold
the body in a single position for a long period of
time. Lack of movement reduces circulation
and causes muscle tension
Holding hands in place
Keeping the head still while reading
Sitting still for long periods of time
Sitting upright without back support
Lifting (Static Loading)
A large percentage of ergonomic injuries are
due to improper lifting. Planning the lift before
attempting it will prevent most injuries (Ando et
When evaluating a lifting task, consider:
1. The weight of the object
2. What position it must be lifted from and to
3. How many times you will need to lift it
4. If there will be twisting involved
5. If there is good footing, and if you can get a good
grasp on the object
Lifting (Static Loading)
Use a step stool or platform to
reach loads above your head
For bulky and oversized loads,
get help or use mechanical
Get a good grip- use handles
Lifting (Static Loading)
Get a firm grip on what you are lifting and be sure you are on solid footing
Squat when lifting something from below the waist. Keep heels down and
feet shoulder-width apart and turned out
Keep the load close to your body
Turn your whole body in the direction you want to move- avoid twisting
Keep your knees bent and lean in the direction of the movement
Let your legs and body weight do the work
Squat to set loads down
NO ONE SOLUTION FOR ALL
People come in all shapes and sizes- what
works for one person may or may not work for
Ergonomics is a puzzle to be put together for
What works today may or may not work later.
We all change due to time and other
ergonomic risk assessment.
Identify types of ergonomic problems
Look at your daily work tasks
Identify one or more risk factors
Review & rethink your work activities/tasks
(including those outside of work).
Identify barriers to solving the problems
Discuss concerns and possible solutions with your
Adjusting work schedules
Modifying job design
Rearranging task order
Changing task assignments
Consult a Physiotherapist, physician or occupational
therapist if warranted.
Identify approaches to overcoming the barriers
Recommend and/or implement solutions.
Try something and if it doesn’t feel comfortable,
discontinue and try something else!
As time passes, try to notice if the problem has truly
Let your supervisor know how well the controls are
You Can Reduce Risk Greatly
Improve body posture and keep a safe body position
• avoid awkward positions
• use tools and equipment correctly
Rearrange work area-
•control your environment,
•use the right equipment in the right position,
•keep work within reach
Change work habits-
•practice and use correct procedures,
•avoid repetition and long duration of a single task
•take frequent breaks
Apply ergonomic principals at home, too
SLIPS TRIPS FALLS
Real slips, trips and falls are not
people are injured and work time is lost
by slips, trips, and falls.
Slips, Trips and Falls
•Hazards that can lead to slips, trips and falls are often
overlooked, even though they cause many injuries
ranging from minor cuts and sprains to disabling injuries
and even death (Aaras 1994, Ando et al 2004).
•Although slip, trip and fall hazards are easily created,
they are also easy to correct.
•Be aware of such hazards, and correct them quickly,
before the next person becomes a victim!
A slip occurs when there is too little friction
or traction between footwear and a walking
surface. Common causes of slips are:
•Slippery floor surfaces
•Liquid, moisture or ice on the floor,
•Food, trash or other small objects
•Oil or grease on the floor
•Footwear without nonskid soles
A trip occurs when a person’s foot contacts
an object or drops to a lower level
unexpectedly, and they are thrown off
Some common causes of tripping are:
Desk or file cabinet drawers left open, objects
protruding into passageways and aisles
Electrical or telephone cords that cross passageways and
Insufficient lighting for walking or working
Furniture that creates
Hazardous floor conditions such as
protruding nails, holes or loose boards,
loose carpet and rugs
Elevator cars that do not level off at
the same height of the floor stopped
Unsafe stairway conditions or use
Materials stored in passageways, aisles and
Floor level changes or hidden steps that may not be
In addition to falls as a result of slips and trips,
you may be injured if you fall from an elevation.
Some causes of falls are:
•Using makeshift items (boxes, buckets, chairs, etc ) to gain
•Not sitting on “4 square” of a chair
•Carrying large or too many items that prevents seeing where
you are going
•Jumping from one level to another
Verhagen A. et al. (2006). Ergonomic and physiotherapeutic interventions for treating work-
related complaints of the arm neck or shoulder in adults. The cochrane Library (3)
Ando, S. et al. (2004). Association of self esitmated workloads with musculoskeletal
symptoms among hospital nurses’. Occupational andEnvironmental Medicine, 57(3):21-16.
Bernard, B. et al. (1994) ‘Job task and psychosocial risk factors for work-related
musculoskeletal disorders among the newspaper employees’. Scandinavian Journal of Work,
Environment and Health, 20(6):417- 426.
English, C. et al. (1995) ‘Relations between upper limb and soft tissue disorders and
repetitive movement at work’. American Industrial Hygiene Association Journal, 27(1):175-
Van den Heuvel et al. (2003). Effects of software programs stimulating regular breaks and
exercises on work-related neck and upper limb disorders. Scand J of Work, Environment and
Health 29(2) pg 106-116.
Viljanen et al. (2003). Effectiveness of dynamic muscle training relaxation training or ordinary
activity for chronic neck pain: Randomised Control Trial. BMJ 327(413) pg. 475.
Schierhout G H, Meyers J E, Bridgers R S (1995) Work related musculoskeletal disorders
and ergonomic stressors in the South African Workforce. Occupational and Environmental
Medicine. 52(1): 46-50.
Aaras A. (1994). The impact of ergonomic intervention on individual health and corporate
prosperity in a telecommunications environment. Ergonomics . 37 (10):1679–96.
Carlton R. (1987). The effects of body mechanics instruction on work performance. American
Journal of Occupational Therapy. 41(1):16–20.
Davis P. et al. (1998). Comparative efficacy of conservative medical and chiropractic
treatments for carpal tunnel syndrome: a randomized clinical trial. Journal of Manipulative
and Physiological Therapeutics. 21(5):317–26.
Westlander G, et al. (1995). Evaluation of an ergonomics intervention programme in VDT
workplaces. Applied Ergonomics. 26(2):83–92.
Hinweis der Redaktion
Signs of MSD are objective physical findings.
Symptoms can vary in their severity depending on the amount of exposure the employee has had. Often the symptoms appear gradually as muscle fatigue or pain at work that disappears during rest. Usually the symptoms become more severe as exposure continues. An example is tingling continues when the employee is at rest, numbness or pain make it difficult to perform the job, and finally the pain is so severe the employee is unable to perform physical work activities.
We will give exercises & stretches for all parts of the body. Perform these at your workstation, at home, or anywhere else.
There are written descriptions for each exercise and demonstrations for some of others.
Get the audience to stand up and do these together.
Blinking and Yawning both produce tears to help moisten and lubricate the eyes.
Focus on a distance object across the room or even outside the window.